The Visible Light Communications (VLC) is a kind of wireless communication technology, which uses the visible light of which the frequency is between 400 THz (the wavelength is 780 nm) and 750 THz (the wavelength is 400 nm) as a communication medium to complete information transmission.
The Visible Light Communication is a wireless access technology, which uses Light Emitting Diode (LED) visible light signals to transmit data. The most important characteristic of the Visible Light Communication is that it combines a LED illumination technology with the name of “green illumination” and provides high speed data transmission without electromagnetism interferences during the illumination, which solves problems of a narrow frequency band and the electromagnetism interferences in a broadband wireless system.
Although the Visible Light Communications has the above advantages, the linear characteristic of the visible light transmission is easy to form a coverage blind area. As shown in FIG. 1, a terminal device enters an area of a target access point from an original access point, and it may cause an access service of the terminal device to be interrupted at that moment. By providing the access switching flow of the Visible Light Communications for the terminal device, the continuous access service can be provided for the terminal device to improve user experience.